Problem: Christopher walked to a hardware store in the evening and, after browsing for 9 minutes, decided to buy a nail for $1.72. Christopher handed the salesperson $1.88 for his purchase. How much change did Christopher receive?
Solution: To find out how much change Christopher received, we can subtract the price of the nail from the amount of money he paid. The amount Christopher paid - the price of the nail = the amount of change Christopher received. ${1}$ ${8}$ ${8}$ ${1}$ ${7}$ ${2}$ ${-\vphantom{0}}$ ${6}$ ${1}$ Christopher received $0.16 in change.